We got into trouble the last time we dared question why so many women in the technology industry get sucked into the public sector. But here goes another one.

We were not expecting someone with the stature of Joanna Shields, Vice President and Managing Director of Facebook EMEA, to be appointed the new chief executive of Tech City – to put it mildly. But that is what was jaw-droppingly announced in the Sunday Telegraph this weekend.

Since its inception, The Kernel has been Tech City’s most reliably ferocious critic. It is a role we have played with pride. We have dissected, derided and denied the claims of this wasteful and incompetent quango week-in, week-out.

This news suggests that we look again at the organisation’s future. With Shields’s appointment, TCIO has effortlessly inherited something it previously lacked: credibility. The organisation may yet prove us wrong with someone like Joanna Shields at the helm.

Make no mistake: this is a coup for the Government. We said it ought to be a woman, but we never for a second imagined that UKTI would bag this woman.

But while the appointment is dramatically and overwhelmingly positive news for Tech City, it is perhaps worth reflecting whether it is good news for Joanna Shields. Because Shields appears with this new appointment to be signalling the end of her private sector career.

Very few people – women, in particular – make it back onto the executive team after accepting such a role. More often, they disappear into single-issue “campaigning”, repetitive panel discussions at conferences and the occasional media appearance.

Perhaps the most high-profile example from the last ten years is Lastminute.com’s Martha Lane Fox, who appears in the papers now and again to address “digital inclusion”, but who is increasingly divorced from the wider industry.

It is difficult to escape the conclusion that the technology industry proper has, with this announcement, lost one of its leading female lights. No longer will Shields credibly be able to claim the top spot on the women in tech lists now she is in a cushy marketing job in a Government department.

The question is: will Shields, like Lane Fox before her, be content with such a predictable life? Will a few board seats and a middling public sector salary hold her interest? Moreover, why is she throwing in the towel while, as the New Statesman might put it, still “at the top of her game”?

After all, Shields’s Facebook share options have most likely vested by now: she is a very wealthy woman and she leaves Facebook with her options safely in the bag and a contacts book unrivalled by perhaps any other woman in the European Internet economy.

Many questions hang in the air. But one thing is certain: for Tech City, and for Shields, the game has changed.